code: def freq_path_process(self, x):
      batch, N, freq, time = x.shape
      x = x.permute(0, 3, 2, 1).reshape(batch * time, freq, N)
      x = self.freq_nn(x)
      x = x.reshape(batch, time, freq, N).permute(0, 3, 2, 1)
      return x.contiguous()
  
imports: import warnings
  import torch
  import torch.nn
  from espnet2.enh.layers.dptnet import ImprovedTransformerLayer
  from espnet2.enh.layers.tcn import ChannelwiseLayerNorm
  from espnet2.torch_utils.get_layer_from_string import get_layer
label_desc: Use image node_id 3 for calling the ATFBlock obj's underlying member method code with example usage: obj.freq_path_process(x) and returns: x